Bluetooth is a novel short-distance wireless connection technology that is open, low in cost, low in power consumption, and capable of replacing a short-distance cable and achieving wireless voice and data transmission. As Bluetooth equipment in a mobile phone is applied more and more widely, a Bluetooth standard is upgraded continuously from V1.0 to V4.1, Bluetooth is applied from a mobile phone terminal to interconnection of wearable equipment, the internet of things and automotive electronics, requirements of industry and users for Bluetooth performance are increasingly high, and particularly, requirements of customers for Bluetooth applicability to multiple application scenarios are increasingly high. The magnitude of Bluetooth performance is a very important index of a high-end mobile phone, which influences the performance of the whole phone and determines success or failure of a product.
Factors influencing the Bluetooth performance include the following several contents.
1. The influence of a maximum transmitting power supportable by Bluetooth on the performance of a transmission distance is large; in a traditional solution, due to limitations of a Bluetooth power class set by software, for example, a maximum transmitting power range of −6 dB to 4 dB under the limit of CLASS2, a software code default power is about 0 dB, and this transmitting power is fixed and cannot be adjusted; and in case of increase of the loss of a radio frequency front end or antenna sharing, attenuation of power from a Bluetooth chip to an antenna front end will be further increased, so the radiation power of Bluetooth will be greatly reduced. Therefore, a maximum linear transmission distance of Bluetooth is limited to be within a range of 10 m, and that is why Bluetooth transmission will be interrupted out of a range of 10 m or in the presence of an obstacle or a phenomenon of sound lag occurs.
2. An ISM band used by Bluetooth is a band open to all radio systems, a frequency range is 2402 to 2480 MHz, and Bluetooth will encounter various interference sources, so Bluetooth adopts a rapid packet acknowledgment technology and a frequency hopping solution to ensure stability of a link and a channel. There are 79 or 39 physical channels of Bluetooth generally, in a transmission process, random hopping is performed on these radio frequency channels via a pseudorandom sequence, and the sensitivity of each channel is different more or less, so if Bluetooth hops to a channel which has a weak signal or is prone to interference, the voice stability and transmission rate of a Bluetooth connecting terminal will be influenced.
3. When a Bluetooth earphone is connected to a mobile phone, if the mobile phone or the earphone is close to a body or a person is in a non-stationary state, such as walking, exercising and turning, due to the influence of antenna directionality, Bluetooth audio transmission may cause an obvious lag phenomenon. Meanwhile, due to a body effect, the Bluetooth earphone is put in a left ear or a right ear, the mobile phone is put on the same or opposite side of the body, and antenna gains and efficiency will be changed under the influence of body absorption, thereby influencing the quality of call voice or audio transmission.
4. When the Bluetooth of the mobile phone is used, an external Wireless Fidelity (WIFI) and Long Term Evolution (LTE) signal stray interference within a same-frequency range exists or Bluetooth will cause an obvious lag phenomenon when an own WIFI and LTE of the mobile phone are initiated, thereby influencing the quality of call voice or audio transmission.
To sum up, any one of the above factors would influence the performance of Bluetooth transmission. However, any effective solution has not been proposed yet in the related art to avoid the influence of any one of the above factors so as to adjust Bluetooth performance to achieve a good communication state.